-------- ------
0 1
1 4
2 16
3 64
Console#
Layer 3/4 Priority
The
Layer 3/4 Priority
page contains links to the following pages:
l
IP Precedence/DSCP Priority Status
l
IP Port Priority
IP Precedence/DSCP Priority Status
You can assign Layer 3/4 priority to traffic in the switch by considering the settings in the Type of Service (ToS) field in the IP header of a frame. The ToS field
can contain an IP Precedence or the more recently released Differentiated Services Code Point (DSCP) value, depending on whether you have DSCP or IP
Precedence-aware devices in your network. You can use the
Layer 3/4 Priority
page to identify IP traffic priorities and map the priorities to the CoS values in
the priority tag of each frame.
The following figure shows the ToS field structure for IP Precedence and IP DSCP.
From the
IP Precedence
section, you can map IP Precedence values to traffic class values. These settings apply to all ports on the switch.
The following options are available:
l
IP Precedence Priority Table
—
Displays a list of IP Precedence values with mapped CoS values.
l
Class of Service Value
—
Maps a CoS value to an IP Precedence value. The number 0 represents low priority and 7 represents high priority.
Click
IP Precedence
in the
IP Precedence/DSCP Priority Status
field to enable this feature.
Each IP Precedence value (from 0 to 7) is mapped to one CoS value (from 0 to 7). The number 0 represents the lowest priority and 7 represents the highest
priority.
The following table shows the default priority mapping.
NOTE:
The switch allows you to choose between IP Precedence or DSCP priority. Select one of the methods or disable this feature.
IP Precedence Value
CoS Value
0
0
1
1
2
2
3
3
4
4
5
5
